German patent application DE 10 2011 102 709 A1 discloses a device for generating sounds that simulate the operating noises of a motor vehicle. This device comprises a real-time-capable processing unit with which operating parameters of the motor vehicle are detected. The channels of a multi-channel sample player are actuated as a function of the detected operating parameters in order to generate the operating noises.
German patent application DE 10 2009 055 777 A1 discloses a method for the synthetic generation of an engine noise, whereby a data memory is employed in which several signal samples having function values are stored. The signal samples are retrieved in a manner adapted to the rotational speed and as a function of detected operating parameters of the motor.
German patent specification DE 197 46 523 B4 discloses a method for generating sounds in motor vehicles, whereby, to start with, the rotational speed of the motor of the vehicle is detected. On the basis of the determined rotational speed, a fundamental frequency of the noise emitted by the motor is calculated. Moreover, the load condition of the motor is ascertained by a load condition sensor. On the basis of the load condition, harmonic components relating to the fundamental frequency are selected, whereby the entire spectrum is raised towards higher loads.
European patent specification EP 0 469 023 B1 discloses a sound-amplifying system for use in a vehicle, comprising a source of stored signals for operating noises of vehicles. Moreover, signal sources serve to provide signals relating to the vehicle operation such as, for example, vehicle acceleration signals, motor operation signals, throttle-valve-position signals and gear shift signals.